The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 11, 2004
Filed:
Nov. 21, 2002
Masahiko Kimura, Kusatsu, JP;
Hirozumi Ogawa, Shiga-ken, JP;
Takuya Sawada, Lausanne, CH;
Akira Ando, Omihachiman, JP;
Abstract
A piezoelectric ceramic composition includes a bismuth layered compound containing Sr, Bi, Nb and a metal element other than Bi having a valence of 3. The bismuth layered compound satisfies the relational expressions: 0.275<a/c<0.5; 0.9≦b/c≦1; 0<x/c≦0.175; and 0.5<(a+3x/2)/c≦0.7, where a, b, c and x represent the molar fractions of Sr, Bi, Nb, and the metal element other than Bi having a valence of 3, respectively. Thus, a piezoelectric ceramic composition mainly containing a bismuth layered compound whose bismuth content is equal to or less than the stoichiometric value and not substantially containing lead and which can be advantageously used for piezoelectric ceramic elements exhibiting a Q -factor sufficient for practical use can be achieved.